Fuel gauge/sending unit

Sam

You may want to check where the rear wiring harness connects to the main, this
is located on the right passenger footwell near the top. You mentioned you
restored your car, there is a chance the green and black wire has pulled from
the connector at that location when you installed the interior.

I had exactly the same the same problem as you described with my 63 sprite,
the green&black wire had pulled out of the connector. I plugged it back in and
had a working fuel gauge.

Greg Higgins